The Symposium was sponsored by IUTAM (International Union of Theoretical and Applied Mechanics). The Scientific Committee of the Symposium consisted of M. J. Lighthill (Chairman) and eight other members from seven countries. The main topics of the Symposium were: (1) high-speed flow of ionized gas; (2) flow with solid boundaries; (3) shock waves; (4) instability and turbulence, and (5) experimental methods.